re.match('com', 'comwww.runcomoob')

re.search('\dcom', 'www.4comrunoob.5com')

一旦匹配成功，就返回一个match object 对象，对象拥有下列方法；

group()  返回被re 匹配的字符串

start()  返回匹配开始的位置

end()    返回匹配结束的位置(返回结果是索引加1，和分片一样，不包括组的结束位置)

span() 返回一个元组包含匹配（开始，结束）的位置

s = re.match('com', 'www.runcoomoob')

print(s)   #None

print(s.span())   #注意位置，不是0－3

Traceback (most recent call last):

  File "C:/Users/Administrator/PycharmProjects/laonanhai/day6_test/s9.py", line 15, in <module>

    print(s.span())   #注意位置，不是0－3

AttributeError: 'NoneType' object has no attribute 'span'

s2 = re.search('com', 'www.runcomoocomb')

print(s2)

#<_sre.SRE_Match object; span=(7, 10), match='com'>  注意前面的找到则不再往后找

s3 = re.sub("g.t", "have", "I get A, I got B, I gut C", 2)

print(s3)    #I have A, I have B, I gut C

s4 = re.subn("g.t", "have", "I get A, I got B, I gut C")

print(s4)    #('I have A, I have B, I gut C', 2)   多了替换次数

s5 = re.split('\d+', 'one1two2three3four4')

print(s5)   #['one', 'two', 'three', 'four', '']    注意最后是''

text = 'JGood is a handsome boy, he is cool, clever, and so on...'

regex = re.compile(r'\w*oo\w*')    #regex 是对象

print(regex.findall(text))         #['JGood', 'cool']

# 无分组

origin = "has fkdghggfhh"

r = re.match("h\w+", origin)

print(r.group())      # 获取匹配到的所有结果

print(r.groups())     # 获取模型中匹配到的分组结果

print(r.groupdict())  # 获取模型中匹配到的分组结果

# has

# ()

# {}

import re

m = re.search("(?P<year>[0-9]{4})", "test 2017abc")

print(m)

print(m.group())

print(m.groups())

print(m.group("year"))

<_sre.SRE_Match object; span=(5, 9), match=''>

2017

('',)

2017

# search()  分组也一样，只是找的方式不同

origin = "has fkdghggfhh"

r = re.match("h(?P<name>\w+)", origin)   #给字典添加key,注意括号！！

print(r.group())      # 获取匹配到的所有结果

print(r.groups())     # 获取模型中匹配到的分组结果

print(r.groupdict())  # 获取模型中匹配到的分组中所有执行了key的组

# has

# ('as',)

# {'name': 'as'}

origin = "has fkdghggfhh hal"

#r = re.findall("(h\w+)", origin)    #无用分组   ['has', 'hggfhh', 'hal']

#r = re.findall("h(\w+)", origin)    #只拿分组里面的东西  ['as', 'ggfhh', 'al']

origin = "hasbbcc fkdghggbbccfhhbbcc halbbcc"

r = re.findall("h(\w+)bbc", origin)  #['as', 'ggbbcfhh', 'al']

r = re.findall("h(\w+)b(bc)c", origin)

print(r)    #[('as', 'bc'), ('ggbbccfhh', 'bc'), ('al', 'bc')]

# 无分组

origin = "hello alex bcd alex lge alex acd 19"

r = re.split("alex", origin, 1)

print(r)        #['hello ', ' bcd alex lge alex acd 19']

# 有分组

origin = "hello alex bcd alex lge alex acd 19"

r1 = re.split("(alex)", origin, 1)

print(r1)   #['hello ', 'alex', ' bcd alex lge alex acd 19']

r2 = re.split("al(ex)", origin, 1)   #重要

print(r2)   #['hello ', 'ex', ' bcd alex lge alex acd 19']